A lost landscape where early humans roamed more than 12,000 years ago has been uncovered beneath the North Sea. A map of the underwater world reveals criss-crossing rivers, giant lakes and gentle hills around which hunter-gatherers made their homes and found their meals toward the end of the last ice age.

The region was inundated between 18000 and 6000BC, when the warming climate melted the thick glaciers that pressed down from the north.

As the waters rose the great plain vanished, and slowly the contours of the British Isles and the north-west European coastline were established. Now the primitive landscape is submerged and preserved, tens of metres beneath one of the busiest seas in the world.

Scientists compiled 3D seismic records from oil-prospecting vessels working in the North Sea over 18 months to piece together a landscape covering 23,000 sq km, stretching from the coast of East Anglia to the edge of northern Europe. They identified the scars left by ancient river beds and lakes, some 25km (15mls) across, and salt marshes and valleys.

"Some of this land would have made the perfect environment for hunter gatherers. There is higher land where they could have built their homes and hills they could see their prey from," said Vince Gaffney, director of Birmingham University's Institute of Archaeology and Antiquity, who lead the project with Ken Thomson, a geologist.

The recreation of the ancient landscape shows that the land beneath the North Sea was probably more than merely a land bridge. People moving north into Europe as the worst extremes of the ice age receded could have lived comfortably on the land, with what is now Britain marginalised and distant.

"People think this was a land bridge across which people roamed to get to Britain, but the truth is very different. The places you wanted to live were the big plains next to the water and the coastline was way beyond where it is now. This was probably a heartland of population at the time," Prof Gaffney said. "This completely transforms how we understand the early history of north-western Europe."

The northernmost point of the map falls just short of the south coast of Norway, where rising water levels swamped the land around 18,000BC.

"This is the best preserved prehistoric landscape, certainly in the whole of Europe and possibly the world," said Prof Gaffney.